Few phylogeographic studies have been undertaken for species confined to narrow, linear coastal systems where past sea-level and geomorphological changes may have had a profound effect on population sizes and distributions. Nevill et al. conduct a phylogeographic analysis of Eucalyptus gomphocephala (tuart), a tree species restricted to a 400 × 10-km band of coastal sand-plain in south-west Australia. Genetic data suggest wide persistence of the species during the Last Glacial Maximum (LGM) and palaeo-distribution modelling gives strong evidence for occurrence of E. gomphocephala westward of the current coastline during the LGM. The study highlights the importance of the inclusion of complementary, non-genetic data (information on geomorphology and palaeoclimate) to interpret phylogeographic patterns.